by: eric reutebuch
Logan Martin Lake Protection Association (LMLPA) gathered in October 2011 for their annual meeting at the Pell City Civic Center on the Cropwell Embayment of Lake Logan Martin. LMLPA volunteer water monitor have been testing sites on the lake and its tributaries since 1996, amassing a database of over 2, 400 water quality records. Monitors have been trained and certified by Alabama Water Watch (AWW) in Water Chemistry Monitoring and Bacteriological Monitoring. The group currently monitors water chemistry at 15 sites and bacteria at 8 sites.
The group became interested in bacteriological monitoring from concerns about apparent sewage contamination entering the lake at multiple locations. The AWW Bacteriological Monitoring training would provide local lake residents the ability to test for E. coli, an indicator of the presence of fecal matter, and to quantify the level of contamination using the EPA-approved AWW procedure. Pell City had been cited by the Alabama Department of Environmental Management (ADEM) for sewage overflows, which was a likely source of sewage entering the lake. The group initiated bacteriological monitoring downstream of suspected contamination source areas on Fishing Creek (site #40) and Blue Spring Branch (Sites #42 and 38) in the fall of 2006.
In 2009, AWW staffers presented bacteria trend graphs for these sites at the LMLPA annual meeting. At that time, trends at the sites showed increasing E. coli contamination to levels unhealthy for human contact (see graphs below). The trend graphs documented and quantified
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The emergence of high levels of E. coli contamination during 2008 in the two streams, Fishing Creek and Blue Spring Branch, emptying into the lake. The LMLPA data confirmed what many lake residents had suspected. E. coli levels as high as 21,000 per 100 milliliters of water were measured in 2008 (levels above 235 per 100 milliliters of water, based on a single sample, have been deemed unsafe for swimming by ADEM). Isabella Trussell, LMLPA Water Monitor Coordinator, advised the public to avoid contact with contaminated waters in these areas (click here for news article in the Daily Home).
During the 2011 LMLPA meeting, updated bacteria graphs of 156 data records (about 50 records per site) were presented for the same sites (see graphs below). This updated data showed dramatic declines in
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in E. coli levels at these sites relative to the unsafe levels reported in 2009. Declines in the bacteria levels coincided with needed repairs in sewer infrastructure. The LMLPA volunteer monitoring data quantified serious water quality problems, served to warn the public of health risks, and documented the resolution of the contamination problems via successful municipal repairs. Job well done!